A tub assembly in a drum-type washing machine includes a tub body having a cylindrical shape forming front and rear edge portions; a ring-type tub cover coupled with the front edge portion of the tub body; a tub back, coupled with the rear edge portion of the tub body, comprised of an outer circumference wall extending horizontally to a predetermined distance with respect to an outer circumference of a circular panel forming a recessed space, the outer circumference wall in tight contact with the rear edge portion of the tub body; and a motor assembly loaded at the recessed space. The tub assembly enables a reduction in tub size and weight, by devising a construction that obviates the need for a bracket for fixing a bearing housing to a tub back and this minimizing a rearward protrusion of the bearing housing and tub back.